Natural oysters up in RI waters

PROVIDENCE, R.I. – At Roger Williams University in Bristol, water rushes into a bathtub-sized tank on a dock at Mount Hope Bay. Dale Leavitt, an associate professor of marine biology, removes a cover revealing quahogs and oysters.

"If you look in here, these are all baby oysters that we've reared up this summer," Leavitt says. "We like to think of them as about the size of a quarter."

Researchers at Roger Williams bred these oysters in a hatchery and when they reach full size they'll be ideal for raw bars.

But they're not what caught the eye of Leavitt and others out on Rhode Island waters this past summer. It's the number of naturally occurring oysters that got their attention. Leavitt says they probably haven't seen levels like this since 1996.

"For example, in the past I've put spat collectors out and we might get one oyster for every five or 10 spat bags," he says. "Where as now, I haven't counted them yet but we're probably going to see somewhere on the order of 20 to 100 oysters per spat bag."

Researchers say the oysters are definitely there but pinning down the reason behind the increase is another story. Some think it could have to do with the pressure the oysters face from predators and improved water quality could play a role too. It may also be the wet early spring followed by hot, sunny weather.

But nobody knows for sure.

"Why this year is better than last year or the year before?" Leavitt asks. "I wish I could answer that question."

Meanwhile, inside a lab at Roger Williams, Leavitt and his colleagues are breeding disease resistant oysters developed at Rutgers University with the goal of moving them to natural water.

Even though these oysters were created in a lab, the hope is that they too could have an effect on natural oyster levels. The idea is that if an oyster can resist disease, it can potentially live longer and spawn more offspring that also produce future oysters.

Leavitt and others will be watching those oysters as they're moved to Mount Hope Bay. If they survive, researchers say there's a chance they could help boost the state's marine economy.

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